The present invention relates to the field of ceiling and wall mounted device supports. More specifically, in one embodiment the invention provides for an improved method and apparatus for securing into place at a ceiling or wall a device or devices.
Often it is necessary to install lights, plant hooks, banners, and other heavy items at the ceiling plane, or to wall mount devices such as receptacles for power, telephone, data, closed circuit cameras, or lights, and other items at the wall plane.
Electrical devices require junction boxes for making electrical connections. One means of supporting an electrical device at the ceiling plane is a crossbar on which an electrical junction box is mounted, as shown in FIG. 1.
FIG. 1 is a view from above a suspended ceiling 14, showing a junction box 10 mounted so as to allow access junction box 10 from beneath a ceiling tile 12. Ceiling tile 12 is one tile in suspended ceiling 14 (detail not shown), and is suspended from a building structure (not shown) by support wires 16 and tee-bars 18. Since ceiling tile 12 is not structurally sound enough to support junction box 10, a crossbar 20 is required to support junction box 10. Crossbar 20 is intended to be a junction box locating support only. As such, the combined assembly of crossbar 20, junction box 10, and a vertical support member 22 do not comprise a load-rated assembly to which devices can be attached unless independent support 16' is provided at junction box 10, which must extend to the building structure. Crossbar 20 and junction box 10 attached to crossbar 20 are free to pivot about vertical support 22, thus being an unstable means for supporting an electrical device. For those regions where seismic activity is a consideration, the combined assembly described must incorporate seismic tie wires (not shown) for rigidly securing the combined assembly into place.
Additionally, crossbar 20 must be located by vertical support members 22 to keep the bottom of the junction box 10 level with ceiling tile 12. Because crossbar 20 is the only means of support for junction box 10 and junction box 10 must be flush with ceiling tile 12, the vertical support members 22 must match the height of the junction box 10.
Even if two crossbars were used to prevent a junction box from pivoting and the junction box were mounted above the crossbars to avoid the height matching problem, the means for support is complicated, since two crossbars are needed, the crossbars themselves are not load-bearing, and the crossbars must be carefully spaced to align with the junction box attachment holes.
Access to an installed junction box is complicated by the fact that the crossbar, or crossbars, prevent access from above, since after installation, the ceiling tile and electrical device will prevent easy access from below.
Another method of supporting an electrical device at the ceiling plane is through the use of threaded rod to which a junction box is attached, as shown in FIG. 2. FIG. 2 is a view from above a suspended ceiling 14 of a junction box 10 utilizing a threaded support rod 24 which is attached to the building structure (not shown) and runs down to junction box 10. Junction box 10 is in turn adjusted to be flush with ceiling tile 12.
Because the space between the building structure and ceiling tile 12 is often occupied with piping, ducts, and wiring (not shown), and because threaded support rod 24 must be kept vertical at all times, this method of support can create conflicts when piping, ducts or the like pass over the vertical space above the point where threaded support rod 24 is to pass.
In regions where seismic activity is a consideration, junction box 10 must also be braced in a splayed manner to restrict movement in the horizontal plane. This is most often accomplished by extending three support wires 25 at 120 degree radial spacing from each other at approximately a 45-degree angle from vertical from junction box 10 at ceiling tile 12 to the building structure. These support wires further compound the interference which occurs between threaded support rod 24 and overhead duct work and the like.
In many instances, a building's structure does not coincide with the desired placement of threaded support rod 24. In such cases, the installation of threaded support rod 24 is complicated by the need to provide supplemental structural support elements such as metal channel which must be secured to the building's structural elements.
While tee-bars which support an acoustical tile ceiling might support a device, the reliance on tee-bars for support would limit the placement of a device to the boundaries of ceiling tiles formed by the tee-bar grid. However, designs and aesthetic considerations often dictate that a device be located within a ceiling tile, such as at the center of a ceiling tile.
Wall-mounted devices share common traits and mounting difficulties with ceiling-mounted devices, however additional difficulties arise where one or more electrical devices must be installed simultaneously within the confines of a space dictated by framing members. One such method for supporting single or multiple electrical junction boxes between framing members is shown in FIG. 3.
FIG. 3 is a view of a framed wall with external and internal coverings removed for clarity. A bracket 26 has multiple junction boxes 10 connected to it together with junction box extension rings 28. Junction box extension rings 28 can be used with or without junction boxes 10, depending on the application. Bracket 26 is secured to wall framing 30 at a desired height using mechanical fasteners 32. The fixed spacing of junction box openings 33 along the length of the body of bracket 26 does not allow for additional junction boxes to be placed at any desired position along the length of bracket 26, instead limiting placement to the four pre-defined openings 33. Furthermore, bracket 26 does not allow for what is known in the trade as a multi-gang junction box.
FIG. 4 is a view of a framed wall with external and internal coverings removed for clarity. A bracket 34 is secured to framing members 30 at a desired height using mechanical fasteners 32, and bracket 34 allows for the installation of single or multiple junction boxes 10 along the length of the bracket 34. However, because junction boxes 10 are mounted to the face of bracket 34, an installer must choose the correct bracket for the trade size junction box 10 which is to be installed. Additionally, bracket 34 can be used only to secure junction boxes 10 into place, and cannot be used to secure extension rings 28 (shown in FIG. 3) into place over the junction boxes, thereby requiring junction boxes for each extension ring 28 used. Attachment of junction boxes 10 to bracket 34 is made through the use of mechanical connectors 32, which are different than the mechanical connectors, typically metal screws, which are generally furnished with junction boxes 10. Thus, additional cost is incurred by an installer of such junction boxes, as provided hardware is wasted while additional fasteners are needed.
From the above it is seen that an improved means for mounting devices at framed ceiling or walls is needed.